Fountain pen



FIG. 1 is a perspective view of the new design for a fountain pen;

FIG. 2 is a side elevation view thereof;

FIG. 3 is another side elevation view thereof oriented at a position180° from the view depicted in FIG. 2;

FIG. 4 is a side elevation view thereof oriented at a position 90° fromthe view depicted in FIG. 3;

FIG. 5 is a side elevation view thereof oriented at a position 180° fromthe view depicted in FIG. 4;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

CLAIM The ornamental design for a fountain pen, as shown and described.